BOSTON
— To gain American citizenship, immigrants must be able to answer such questions as: What was the 49th state added to our Union? What color are the stars on our flag? And who wrote the Star Spangled Banner?

Sound trivial? The US government thinks so, and plans to roll out a new pilot test this winter.

It will continue to be an oral test, conducted in English, and will have 10 questions. Six correct answers will earn a passing grade. But the content, which is tightly under wraps, is expected to shun simple historical facts about America that can be recounted in a few words for more explanation about the principles of American democracy, such as freedom.

The changes raise the bar – critics say too high – for immigrants to show not only that they care enough to study for a test, but also that they understand and share American values. Behind the shift is rising anxiety among Americans about high levels of immigration and European troubles with large, unassimilated communities, say observers.

"Whenever there is a large number of immigrants, people talk about having an assimilation policy," says John Fonte, a senior fellow at the Hudson Institute, a think tank in Washington. "We've always had an Americanization policy of some type [but] we haven't so much in the last 20, 30 years.... I'd see this as continuing that tradition, which Europe did not do."

Immigrant advocacy groups are wary of the changes, which coincide with a review at the US Citizenship and Immigration Services (USCIS) agency that is expected to call for a substantial hike in the $400 citizenship application fees.

"The administration is putting up [another] wall to citizenship for immigrants between a longer application process, higher fees, and what may very well be a more difficult test," says Ali Noorani, of the Massachusetts Immigrant and Refugee Advocacy Coalition. "Immigration is a culture war today. Is the way to lessen the rhetoric in that war to administer a new test?"

Mr. Noorani is withholding final judgment on the changes until they become public Nov. 29.

The revisions are an effort, say officials, to make the test a more teachable moment – without making it more difficult. The questions and answers – which will be publicly available – are expected to draw on concepts in the nation's founding documents. The pilot will be rolled out on a trial basis in 10 cities across the country, including Boston. If participants fail, they can retake the regular test, a test that very few fail.

"Look at the Bill of Rights and some of the values and rights that are enshrined in [it]. Those could possibly be test question topics [as could] the meaning of democracy, the meaning of freedom," says Shawn Saucier, spokesman for the USCIS, adding that some immigrants "come from a culture, a government, a society that is completely removed from our concept of government."

Historians with the USCIS explain that officials have long tried to determine whether a potential citizen feels "attachment" to America. For years that has been interpreted as demonstrating knowledge of the country. The purchase of war bonds and participation in wartime recycling were also seen as proof of attachment.

Canada offers a test similar to the current US one. Other Western nations that are concerned about assimilation are now requiring tests, says Mr. Fonte, and some are taking it a step further. The Netherlands shows a video featuring gay men and beach-going women to ensure that newcomers – particularly Muslims – will be comfortable with the country's liberal social mores. Australia is reportedly considering a test with questions about the sport of cricket.

The changes in the US bring the test closer to the notion sweeping Europe that gaining citizenship requires subscribing to a set of shared values – though no one is likely to be quizzed about the ins and outs of baseball any time soon.

"The receiving nations have been more or less acquiescent – and in a certain sense dissuaded – from foisting expectations of robust civic attachment on the part of the newcomers. And that has had consequences," says John Keeley at the Center for Immigration Studies, citing the terror plots in Britain. "Now we are reconceptualizing what our expectations are."

Fred Tsao, of the Illinois Coalition for Immigrant and Refugee Rights, doubts attachment can be discerned from a test, and blames some of Europe's troubles on unwelcoming policies. His organization joined more than 220 immigrant groups in sending a letter to the USCIS, stating concerns that the new test will raise the bar too high for those with less education.

Both sides agree that citizenship tests are not the only part of assimilation. "For somebody who has come to America for political or religious freedom, every single day is a learning moment, every single day is a moment to cherish. The assumption that a test is going to capture all of that and make everybody get along is a little bit delusional," says Noorani.

Still, the citizenship process has been meaningful for many immigrants, experts say.

"It's valuable as a ritual. Just like someone who is [undergoing] a first communion or a bar mitzvah, they are learning something beforehand, they are going through this process, and there's a ritual or a ceremony at the end ... that's very emotional for people," says Fonte.